Abstract
Laser-Doppler anemometer measurements upstream and in the wakes of vortex breakdowns of bubble and spiral types are described. Spectral analysis of the data indicates prominent oscillations in the wakes at less than 10 Hz. These oscillations correspond closely to theoretical predictions of the linearly most unstable normal modes of the time-averaged mean flow profiles. The oscillations are more energetic, and vortex core expansions are greater for flows with a bubble form of vortex breakdown, which is therefore regarded as the stronger form of breakdown.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2053-2064 |
| Number of pages | 12 |
| Journal | Physics of Fluids |
| Volume | 22 |
| Issue number | 11 |
| DOIs | |
| State | Published - 1979 |
ASJC Scopus subject areas
- Computational Mechanics
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Fluid Flow and Transfer Processes